1. Grizzly Bear (Ursus arctos horribilis): Powerful predators encountered in the Rocky Mountains and along the Missouri River.
2. Black Bear (Ursus americanus): Smaller and more common than grizzly bears, found in both forested and open areas.
3. American Bison (Bison bison): Massive herbivores that roamed the Great Plains, providing a vital food source for the expedition.
4. Pronghorn Antelope (Antilocapra americana): Fast and graceful herbivores found on the plains, prized for their lean meat.
5. Bighorn Sheep (Ovis canadensis): Sure-footed mountain dwellers encountered in the Rocky Mountains.
6. Prairie Dog (Cynomys spp.): Social rodents that lived in extensive colonies on the plains, a potential food source.
7. Wolf (Canis lupus): Fearsome predators that sometimes threatened the expedition's livestock.
8. Coyote (Canis latrans): Smaller relatives of wolves, often seen on the plains.
9. Elk (Cervus elaphus): Majestic antlered ungulates found in forested areas.
10. Mule Deer (Odocoileus hemionus): Smaller deer found in more arid environments.
11. White-tailed Deer (Odocoileus virginianus): Common deer found in forested regions east of the Rocky Mountains.
12. Beaver (Castor canadensis): Semiaquatic rodents known for their dam-building abilities, valuable for their fur.
13. Otter (Lontra canadensis): Agile aquatic mammals found in rivers and streams.
14. Cougar (Puma concolor): Powerful feline predators, also known as mountain lions or pumas.
15. Bison calf (Bison bison calf): The calves of American bison, prized as a source of food.